Oral sulfate solution versus low-volume polyethylene glycol for bowel preparation: Meta-analysis of randomized controlled trials

Optimal bowel preparation for colonoscopy

There is robust evidence to indicate a strong correlation between the bowel preparation status and adenoma detection rate (ADR), which directly impacts the incidence and mortality rate of postcolonoscopy colorectal cancer. Therefore, improving bowel preparation has been of increasing interest. In Japan, commercially available bowel preparation agents include polyethylene glycol, oral sodium sulfate, sodium picosulfate-magnesium citrate, magnesium citrate, and oral sodium phosphate; each has its own strengths and limitations. The timing of administration can also influence the efficacy of bowel preparation and patient tolerability. Furthermore, meta-analyses have suggested predictive factors for inadequate bowel preparation. A detailed understanding of these factors could contribute to reducing the need for repeat colonoscopy within 1 year, as recommended for patients with inadequate bowel preparation. Recent advancements, such as oral sulfate tablets, present promising alternatives with higher patient satisfaction and ADRs than traditional methods. Achieving optimal bowel preparation requires enhanced instructions, individualized regimens, and a comprehensive understanding of patient backgrounds and the characteristics of various bowel preparation agents. This article provides a concise overview of the current status and advancements in bowel preparation for enhancing the quality and safety of colonoscopy.

Oral sulfate solution versus polyethylene glycol for bowel preparation before colonoscopy, meta-analysis and trial sequential analysis of randomized clinical trials

BACKGROUND

This study aimed to compare oral sulfate solution (OSS) with polyethylene glycol (PEG) for bowel preparation before colonoscopy.

METHODS

A literature search was performed on PubMed, Ovid, and Cochrane Databases for randomized clinical trials (RCT) comparing OSS with PEG for bowel preparation before colonoscopy. The last search was performed on 22 August 2023. The primary outcome was the quality of bowel preparation. The outcomes were compared by meta-analysis and trial sequential analysis (TSA).

RESULTS

A total of 14 RCTs with 4526 patients were included. OSS was comparable with PEG regarding adequate bowel preparation [P = 0.16, odds ratio (OR) = 1.19, 95% confidence interval (CI) [0.93, 1.51], I2 = 0%]. However, OSS showed obvious priority in excellent bowel preparation (P < 0.001, OR = 1.62, 95% CI [1.27, 2.05], I2 = 0%) and total Boston bowel preparation scale (BBPS) [P = 0.02, weighted mean difference (WMD) = 0.27, 95% CI [0.05, 0.50], I2 = 84%]. Additionally, the detection rate of polyps (P = 0.001, OR = 1.44, 95% CI [1.15, 1.80], I2 = 0%) and adenoma (P = 0.007, OR = 1.22, 95% CI [1.06, 1.42], I2 = 0%) was significantly higher in the OSS group. The two groups showed comparable incidence of adverse events except for a higher incidence of dizziness (P = 0.02, OR = 1.74, 95% CI [1.08, 2.83], I2 = 11%) was indicated in the OSS group. Moreover, OSS was associated with a higher satisfaction score (P = 0.02, WMD = 0.62, 95% CI [0.09, 1.15], I2 = 70%). In the TSA, the cumulative Z-curve crossed both the conventional boundary and trial sequential monitoring boundary and the required information size has been reached for excellent bowel preparation and total BBPS.

CONCLUSION

The current data demonstrated that OSS was associated with better quality of bowel preparation. More clinical trials are still needed to confirm other outcomes.

The Efficacy of 480 ml Oral Sodium Sulfate for Improving Insufficient Bowel Preparation of Colonoscopy with High-Concentrated Polyethylene Glycol

Objectives

Oral sulfate solution (OSS) is used for bowel preparation (BP) during colonoscopy. The way of taking this agent can be used a same-day regimen (only on the day of colonoscopy) and split regimen (the day before and on the day of colonoscopy) for receiving it. In this study, we analyzed the efficacy of a same-day regimen of 480 ml OSS for insufficient bowel preparation (BP) with high-concentrated polyethylene glycol (H-PEG).

Materials and Methods

This multicenter retrospective study was conducted from December 2021 to December 2022 at three related institutions on patients aged ≥ 20 years with a fair or poor Aronchick score of BP with 1 l H-PEG in previous colonoscopy. All patients received a low-residual diet and 10 ml of 0.75% picosulfate sodium a day before the colonoscopy and 480 ml of OSS and ≥1 l of water 3 hours before the colonoscopy. We analyzed the rate of improvement with OSS compared to H-PEG and other efficacies, and adverse events (AE).

Results

We evaluated 125 cases (77 males) with an average age of 72.1 ± 8.8 years. The completion rate of 480 ml of OSS was 97.6% (122/125). The improvement rate of BP showing good or excellent score with OSS was 70.4% (88/125). Compared OSS with previous H-PEG, the insertion time (min) was 7.0 ± 4.8 vs. 8.1 ± 6.0 (p = 0.01), and the adenoma detection rates were 67.2% vs. 63.2% (p = 0.05). The cleansing time (min) was 131 ± 46 vs. 165 ± 53 (p < 0.01). The rate of AE with OSS was 10.4% (13/125). There were no significant differences about AE in age and gender. The tolerance of OSS compared with H-PEG (good/similar/bad) was 72.0%/24.8%/3.2% (amounts), 26.4%/39.2%/34.4% (taste), and 76.8%/10.4%/12.8% (overall preference), respectively.

Conclusions

The same-day regimen of 480 ml OSS effectively improved the insufficient BP of 1 l H-PEG.

Oral sulfate solution benefits polyp and adenoma detection during colonoscopy: Meta-analysis of randomized controlled trials

OBJECTIVES

Although oral sulfate solution (OSS) has been revealed to be not only safe and efficacious but also noninferior to polyethylene glycol with ascorbic acid (PEG + ASC), it is unclear whether OSS can ultimately increase the polyp detection rate (PDR) and adenoma detection rate (ADR). We performed this meta-analysis to estimate the effect of OSS on PDR and ADR during colonoscopy.

METHODS

We searched PubMed, EMBASE, and the Cochrane Library to identify relevant randomized controlled trials (RCTs) investigating the comparative effect of OSS versus PEG + ASC on the PDR and ADR during colonoscopy. Cecal intubation time (CIT), cecal intubation rate (CIR), and bowel preparation score were also evaluated. Review Manager (RevMan) version 5.3.0 was used to perform statistical analysis.

RESULTS

Eight RCTs involving 2059 patients fulfilled the selection criteria. Meta-analysis suggested that OSS significantly increased the PDR (47.34% vs. 40.14%, risk ratio [RR] 1.13, 95% confidence interval [CI] 1.03-1.24, P = 0.01) and ADR (44.60% vs. 38.14%, RR 1.17, 95% CI 1.03-1.33, P = 0.01) during colonoscopy. Subgroup analysis showed that the beneficial effects of OSS on PDR and ADR were consistent among patients with mean age >55 years and with body mass index <25 kg/m² receiving outpatient colonoscopy, morning colonoscopy, and the 2-L bowel preparation protocol. Meanwhile, patients receiving OSS had a beneficial bowel preparation score.

CONCLUSION

Compared with polyethylene glycol-based regimens, the OSS bowel preparation regimen significantly increased the PDR and ADR in patients undergoing colonoscopy.